multiple-inheritance

I would like to make use of few methods from couple of my old tested classes into my new class that I am building. Unfortunately, C# does not support multiple inheritance. How do I reuse code from these old classes? Do I just create them as member objects? or Do I have any other options? Generally, using composition instead of inheritance is the way forward, yes. If you could give a concrete example of the kind of thing you mean, that would make it easier to help find the appropriate approach though: it's not always the same. Using them as member objects should be a good idea. Then you can

Suppose you have two classes X & Y. You want to decorate those classes by adding attributes to the class to produce new classes X1 and Y1. For example: class X1(X): new_attribute = 'something' class Y1(Y): new_attribute = 'something' new_attribute will always be the same for both X1 and Y1. X & Y are not related in any meaningful way, except that multiple inheritance is not possible. There are a set of other attributes as well, but this is degenerate to illustrate. I feel like I'm overcomplicating this, but I had thought to use a decorator, somewhat likeso: def _xywrap(cls): class _xy(cls):

Problem: We know that Java doesn’t allow to extend multiple classes because it would result in the Diamond Problem where the compiler could’t decide which superclass method to use. With interface default methods the Diamond Problem were introduction in Java 8 . That is, because if a class implements two interfaces, each defining the same default method, and the implementing class doesn’t override the common default method, the compiler couldn’t decide which implementation to chose. Solution: Java 8 requires to provide an implementation for default methods implemented by more than one interface

While looking at some OOP materials, I thought of this question which confused me a little bit: Consider having the following interface,abstract class, and a concrete class: package one; public interface A { void doStuff(); } package one; public abstract class B implements A { public abstract void doStuff(); } class C extends B{ public void doStuff() { } } Class C won't compile unless it provides an implementation for method doStuff() . The question here: 1-Is doStuff() method in class C an implementation to the interface A 's method, or it is for the abstract method in class B ? to be more

(Please note: knowledge of the trading card game Magic: The Gathering will be a plus here. Sorry, I don't know how to put it any easier.) I have hit upon a problem using Java , which I'll describe as follows... I have a fundamental class called Card with all the following attributes: public class Card{ String Name; String RulesText; String FlavorText; String Cost; int ConvertedCost; String Rarity; int Number; } The Permanent class extends Card, and is extended in turn by the classes Creature, Planeswalker, Artifact, Land and Enchantment. As of yet, among them, only the first two have fields of